curtis c

My Feedback: (3)

Looking for help, I am some what new to electrics in the larger planes and have had a ESC burn up in about three minutes. This is my set up G60 motor, 80amp ESC, 5000mah 6s-20-30c. When I plugged into the battery there was a small arc. I stopped and check every thing to confirm all connections were correct. Then proceeded to plug a much smaller battery. No arc and after going through the start up of the ESC every thing seemed fine. However this was a very small 1200mah battery but enough to bind the receiver and check the servos and see that the motor was ready. Every thing check out fine. Now I plugged in the larger bat. (5000mah 6s) still a small arc but not being familiar with bats this large I went ahead. Every thing seemed fine I tested the motor ran up the power. Very strong. On the second power up to hold the plane up to see if there is enough power to hover a small chirp that sounded like it came from the motor. Powered down waited a minute, thought about what the noise was and then the ESC burned like I lit a flare. Did I mention that this is a Hobby King ESC, Motor, and Battery. I think the ESC is bad and had a small direct short that was causing the arc when I plugged it in. Please let me know what you guys think. Thank you.

guver

My Feedback: (325)

From what I see what you wrote and the pics, I agree with you that the esc ,,,, never mind let me type what I don't agree with. That is the only part I don't agree with is that the small arc you heard was an internal short. I think they all do that and the higher the voltage the more pronounced is the arc. So , I think your esc just went bad.

I have a few redbricks , but haven't tried them yet. They don't have the best reviews of course. What do you suppose your current was when WOT when it burnded up?

curtis c

My Feedback: (3)

Guver,

Thanks for the response. You are probably correct about the spark. This is my first battery of this size and I am still learning. I don't know the current at WOT however it did burn up while not running the motor at all. It was plugged in but was powered down. My fear is that I am missing something or have something set up rong with with ESC. I don't really see how but as we move into larger power supplies like this the risk of something going rong as greater consequences. I did run my end points up to max on the throttle. I don't think this should effect the esc? Do you? When I first set it up they were down and it would hardily power up. That is the only thing I can think that could have been user error.

guver

My Feedback: (325)

No, I don't think the endpoints would affect it in any way (maybe cause it not to go to WOT) I usually like to adjust my endpoints and trim on throttle without a prop because I use many esc that do NOT allow the throttle endpoints to be programmed and many TX are different. Many other escs that I use set the points EVERY time they are power up. A few of mine set once and then stay that way. A lot of them that are not settable seem to require me to use 100% at idle and 120% at WOT. I wish I knew what the redbrick ones required.

I'm going to calc your current on a calc and estimate it. http://flbeagle.rchomepage.com/softw..._imperial.html Maybe you can do it. I needed the prop size. It will be a good guess.

flyinwalenda

My Feedback: (5)

Yep...looks like the ESC let the smoke out !
What is missing from this riddle is ....what size prop were you running ? 
I doubt that you exceeded 80amps as the motor can only take 60 amp bursts according to the specs so if your set-up is over amped the motor should have went out before the ESC.
The spark you are seeing is typical of all larger battery set-ups. They all spark/arc when plugging in as the esc is quickly charging the caps inside it. To prevent this you can add a resistor and/or a resistor with a push button. This way the resistor slows down the charge to the caps and will lessen or prevent to spark as you plug the battery in.
If you were not over amping then the esc may have been faulty but before you fly again you should buy or borrow a watt meter and test your set-up on the bench to see exactly what amperage you are drawing.

curtis c

My Feedback: (3)

I am using a 16-10 e The spark does not bother me unless it is not supposed to be there. I understand what you are saying about the caps charging when I plug in. When you say (Guver) that you set your end points with out a prop are you running the motor with out a prop? Is there a concern of overspeed? If you could give me a simple test procedur I have a multi meeter. Thank you.

guver

My Feedback: (325)

Yes, I run it full speed without a prop for a few seconds to make sure that it goes to full speed. I have no concern of overspeed since I'm never close to max rpm. I just run it full speed while listening for an increase while I run the endpoint and/or trim UP. A certain brand of esc ALWAYS need over 100% to reach WOT.

curtis c

My Feedback: (3)

I would also like opinions on the battery that I am using in this setup. It seems to have plenty of power that I want but it is seems very heavy. I am considering ordering another but 4000mah 5s 30c . Hoping to achieve 7 to 8 min. flights. Thank you.

guver

My Feedback: (325)

web-o-calc estimates about 50 amps for that prop and motor. I'd surely think that the 80 amp esc would've been ok normally. Hard to tell now.

For the battery a 4000 might be fine as long as it's a good quality pack (probably not a turnigy)

I'm no expert at power systems because I'm rather new to doing planes , but I sure don't see any red flags with your set-up. It's entirely possible that the esc is just grossly over-rated or was faulty. Your set-up is at least twice as powerful as any of mine. My largest is a 3s with about 400 watts. I have my hands full with that. [X(]

mighty9

My Feedback: (10)

My opinion is that its over propped. You need a watt meter to check for sure. The calculators are fine if you have all the data for a proper input. You need motor idle amps, internal resistance and battery internal resistance to calculate properly. We have similar setups on planes and on 6s 3300 turnigy nanotech batteries we get 6 to 8 minutes of flight time. We are running 15x7 props and can get over 60 amps on the motor. We have numerous turnigy batteries and they are long lasting . I have several 40 size as well as 30cc conversions running now. All with turnigy batteries. I have a 50cc Bill Hempel cub on 10s and get over 20 minutes flight time. The spark is normal on anything over 4s .Its just the capacitors charging. I have had several red brick esc failures and will no longer use them. When they burn like your did its usually from over amp draw. If there is anyway i can help let me know id be happy to try and answer any questions you have.

flyinwalenda

My Feedback: (5)

Yes, the prop you are using is probably on the bleeding edge for that motor. I am wondering now if you blew/shorted the motor first which in turn overloaded the esc and burned it.
If you have another esc (30 amp or so) I would test the motor first (no prop) with a 3 cell lipo and make sure it's OK.
If the motor seems OK then the esc could have had some bad solder joints or a heat sink shorting out a transistor and the high amps and heat just brought everything together and did it in. Try another brand of esc and get or borrow a watt meter .

curtis c

My Feedback: (3)

Thanks for the feed back this is very helpful. I don't have another esc this large so I am going to have to order one. I had in mind going to one a little larger like 90-100 amps. Do you all think that is necessary to prevent this from happing. I was under the belief that a 80 amp would be enough. I would like to be able to hover this plane so I might need a larger motor in the future. So maybe it will be a good idea to get the larger esc now. Will a larger esc rob power from the motor?

Would a 16x8 be more in line for my current set up? Or do I need to move down to a 15x10?
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Is there a thread that talks about checking the with a watt meeter. I do have one but not familiar how to test.

chuckk2

I had a brand new "blue" 85A speed control go up in a cloud a couple of months ago.
Funny thing was that I had previously tested it with a 5Ah 6cell LiPo with and without the prop at least three times.
The day that it failed, on what was supposed to be the last ground test before a maiden flight, was when it went up in smoke.
We think that the BEC regulator chip failed first, due to the fact that it was blown totally off the remnants of the PC board.
Heat was enough to melt the solder on the battery and motor connections on the PC board, char the plane structure above the
ESC, melt covering, and make the plane stink. (New car fragrance spray, followed by grey primer sort of solved the smell problem.)
The battery current just before failure was calculated to be well under the 85A rating, if slightly above the motors 20 sec rating.
We replace the 85A ESC with a 75A Castle ESC rated at up to 8 cells. So far, so good.
I'd used the 85A ESC (other unit) in another plane without a problem. (It had a 4cell LiPo, not a 6.)
The only significant considerations concerning use of a large ESC.
Weight, Cost, Size, Power pin and Wire size
It's possible that throttle resolution/control/response might be more course. (This seems to very with brand/model)

mighty9

My Feedback: (10)

A 16x8 sounds more reasonable .Id go with an 80 amp esc minimum.Also i dont use the built in bec .A liFe battery adds little weight and solves the bec overdraw issues. I have seen more than 1 of the red brick esc let the smoke out just because they wanted to. I would suggest you go to heads up rc and look at Jeffs esc. He is a great guy and has the best customer service bar none.This link may give you some needed info on the watt meter.

http://www.rcgroups.com/forums/showthread.php?t=1126508

flyinwalenda

My Feedback: (5)

Yes. Always a good idea to install an outboard BEC or a separate battery for the receiver on larger electric set-ups. If the plane was in the air when this happened it might be in a bag now as you would have lost all control.
Also at this point I'd forget about trying to hover the plane and spend more time getting it set-up just to properly fly. You can tweak it later on.

raptureboy

The answer to the problem is HOBBYKINGyou may get what you pay for and you may not and good luck getting them to owe up to it.

zacharyR

My Feedback: (5)

how did that new smoke system work out ?

fly210sv

My Feedback: (1)

Looks like hobby king Red Brick with Turnigy motor. I have same setup. I believe that motor tops out at 5 cells. Also, Program the red brick for a 6 pole motor. Do not use the programming guide that came with the instructions. You can download it from Hooby King. The factory default is 4 pole. Although the motor will run, the esc will get blazing hot. My experience with HK esc's is less than stellar. That motor however is great. Running it on 5 cells will work well.

guver

My Feedback: (325)

http://www.hobbyking.com/hobbyking/s..._60_Glow_.html Is this the motor? If so it says 7s and 40 amps max. I can believe 7s max , but 40 amps max seems very conservative. Hmm, maybe that is about right 1kw and 40 amps x 25 volts?

fly210sv

My Feedback: (1)

Sorry about that. Must have been the drugs. I would still reprogram the esc. it really cools those red bricks down..

curtis c

My Feedback: (3)

Thanks for the input guys. The fire show was spectacular when it smoked next time I will try it on a night flight.[:@] By the way HK did just own up to it as they have on some other issues I have had. They applied a full refund to my account in just under 5days from when I contacted them. This same Model 12 Pitts came with a crack in the cowl that they have replaced for me. I know the risk of buying from HK but I am still ahead right now. If this failure was during a flight I might think different. But I don't want to get that debate started here. I like the idea of a stand alone BEC. Same redundancy that I run in my gassers with two batts and to switch set ups. As I said I am still learning the set up with elec. So should I specify that when buying the ESC or does it not make a difference?

I will order some smaller props and test what it draws on the motor. Can I use props that I use on glow engines or do they have to be specific for elec? This quite a learning curve. I hope it worth it.

Sounds like using a larger ESC does not rob power. It is just the concern of weight and cost? I think I will go to at least a 85amp.

curtis c

My Feedback: (3)

So I have a credit with HK now because of this ESC that smoked. I am considering this one give me your opinions . http://www.hobbyking.com/hobbyking/s..._w_3A_BEC.html

Let me know what you guys think. I was under the assumption that it did not matter how big the battery is. The motor will take as much power as it needs. Bigger is better except for the weight penalty? Is this not true?

mighty9

My Feedback: (10)

As stated before its a crap shoot with HK some items are great some are not.They seem to have taken care of you so far. Keep in mind you can get an esc with bec and just remove the redwire from the receiver end to disable the onboard bec. I myself would look into an HV esc so you had some more headroom for different props and motors .It may be in your future that you need more motor than what you have now.I know you want to use that credit but i would look into the HOBBYWING line of Hv esc. I have 7 or 8 of them now and not had one issue. Also another option is the HEADS UP RC line of esc. Great prices and customer service that is the best in the business.

mighty9

My Feedback: (10)

As for the battery size it will dictate flight times and weight for balance. So if a big battery helps with Balance then its ok .If it hurts the cg then the longer flight time isnt a plus. The motor is capable of drawing MORE than it needs so be careful with prop sizes. As a rule as the cell count goes up the prop size goes down. I have a couple systems that draw the same amps and output the same watts .One on 8sand the other on 10 s.The 8s runs a 20 inch prop and the 10s runs a 17 incher.Its not always an easy formula to figure out. With moto calc and the correct data inputs you can get very close though.

2walla

My Feedback: (10)

Be careful with the motor. Even testing it wit a 3cell,,,if it has a direct short in it somewhere it will fry the next speed controller too. Look the wires over carefully.. I let the smoke out of a couple of esc due to some small abrasions on the motor leads that allowed it to short.